In the past, there has been known techniques of managing power to be used by multiple power loads. For example, when a total power consumption of multiple power loads exceeds contract power, this fact is notified, and current flows to predetermined power loads and distribution circuits are interrupted (see JP 2009-130973 A (hereinafter referred to as “document 1”), for example).
The power management system disclosed in document 1 is a system for monitoring power consumptions of multiple power loads and controlling the multiple power loads. When detecting an overcurrent through a main breaker, to reduce a power consumption of an electric device with a high rank of controllability or interrupt consumption of power by the electric device, this power management system disclosed in document 1 controls the electric device.
However, the aforementioned prior techniques are techniques for responding to an event where the main breaker trips or an event where the total power consumption of the multiple power loads exceeds contract power or predetermined peak power, in a case where the multiple power loads are allowed to use power freely. In summary, the prior techniques aim to solve a problem occurring when the total power consumption has exceeded the upper limit power. Hence, there is a problem that the total power consumption actually exceeds the upper limit power.